Collapsible t-square



Nov. 22, 1955 B. s. SPEAR, JR 2,724,184

COLLAPSIBLE T-SQUARE Filed Feb. 11, 1953 28%29 5 l3 #9 INVENTOR.

COLLAP SIBLE T-SQUARE Byron G. Spear, Jr., Sioux City, Iowa ApplicationFebruary 11, 1953, Serial No. 336,224

7 Claims. (Cl. 33-112) My invention relates to a T-square construction.

An object of my invention is to provide a T-square which can becollapsed to a minimum sizewhereas such T-square can be convenientlycarried in such reduced size either in a small compartment, briefcase,or otherwise.

A further object of my invention is to provide a T- square constructionwith collapsible characteristics and yet which maintains a true edge,and also includes certain features to maintain the necessary rigidity ofthe T-square.

A further object of my invention is to provide a T- square constructionhaving collapsible characteristics, which. is simple in construction.

With these and other objects in view, my invention consists of theconstruction, arrangement, and combination of the various parts of mydevice, whereby the objects contemplated are attained, as hereinaftermore fully set forth, pointed out in myclaims, and illustrated in theaccompanying drawings, in which:

Figure l is a plan view of a preferred type of the T- square of myinvention,

Figure 2 is a side elevation of Figure 1,

Figure 3 is a detail,

Figure 4 is a detail,

Figure 5 is a detail,

Figure 6 is a plan view of a modified form,

Figure 7 is a side elevation of Figure 6,

Figure 8 is a detail,

Figure 9 is a detail, and

Figure 10 is a side elevation of the modified form in its collapsedcondition.

My invention contemplates the provision of a T-square which can beconveniently collapsed either by detaching sections thereof or byfolding the same to a minimum space, so that unduly long T-squares canthereby be rendered as compact as possible, so that they can betransported conveniently. My invention also contemplates the provisionof providing rigidifying members in conjunction with the collapsiblefeatures.

I have used the character 10 to designate the upper portion of the headof the T-square, and I have used the character 11 to indicate the lowerportion which rests against the drawing board edge, having the edge 12for this purpose. I have further used the character 13 to designate thecentrally positioned flat T-square edge member which includes theportion 14a having the same contour as the members 10 and 11 and beingattached therebetween.

The member 13 includes a recessed centrally positioned cavity 14, andreceived within the cavity 14 is the tongue 15 which is an extension ofthe further member 16. The member 16 also includes a similar cavity 14in which is snugly received the further tongue 15 which is an extensionof the further section 16. The sections 13 and 16 include the drawing orguide edges 17, these edges being in exact alignment for the necessarypurposes. Attached to the various sections 13 and 16 are the smallbosses 18, and received through these bosses is the lengthened bracingrod made up of a plurality of sections 19, these sec- United StatesPatent 0 "ice.

2,724,184 Patented. Nov. 22, 1955 2 tions including the threadedcavities 20 and studs 21, this arrangement permitting. the sections 19to be screwed together, or unscrewedas desired.

Terminating the end section 19 is. a knurled expanded turning member 22.The inner section 19 terminates at the threaded portion 23 which isthreadbl y engaged at 24 within the head portion 10. The end section rod19 also includes a small hole 25.

It will now be observed from the foregoing construction in the conditionshown in Figure 1, the T-square is rigid, since the closely fittingtongues and cavities will be firmly engaged, and since the member 22 isfirmly turned against the end boss 18 until the threaded engage.- mentsat 23 and 24 firmly secure all of the sections together. The T-squarecan thus be used in an entirely natural manner without interference.However, when it is desired to collapse the arrangement, any smallpointed tool or rod is inserted in the hole 25, and the jointed sections19 are rotated until the threaded engagement at 23 and 24 is slightlyloosened. The member 22 is then grasped and rotated still further whichwill draw the member 19 out of the threaded opening thus permittingcomplete removal of the section members 19*, after which the sections 16can be pulled apart, so that they can lie adjacently to the head andsection 13. The sections 19 can then be unscrewed and these sections canalso be placed adjacently to the other sections, thus providing acompletely collapsed condition, fulfilling the advantages abovementioned. The threads on the stud 21 are right hand threads as are thethreads on the member 23, so that they will tighten in the samedirection. The use of the opening 25, however, will loosen thearrangement before the tightly engaged threads between the sections,thus providing the result above mentioned.

Figures 6 to 10 illustrate a modified form of my invention wherein Iemploy similar characters for similar parts. The section rods 19 are thesame as well as the threaded engagement with the member 10 except thatthe bosses 18 will only be required in approximately the position shown.In this construction, I use the pairs of hinges 26 and 27. It will benoted that the hinges 26 are closely adjacent to the sections whereasthe hinges 27 are spaced a fairly substantial distance above thesections. The hinges 27 include the extending portions 28 and 29 forattachment to the sections, the lower hinges 26 having the attachingportions 30.

In this latter construction the rods 19 can be disassembled in the samemanner, after which the various sections are then folded until theyoccupy the position shown in Figure 10, the lengthened hinge 27 allowingthe end section to fold in place due to the space thus provided.

It will now be noted that I have provided the advantages mentioned inthe objects of my invention with fur ther advantages being apparent.

Some changes may be made in the construction and arrangement of theparts of my invention without departing from the real spirit and purposeof my invention, and it is my intention to cover by my claims anymodified forms of structure or use of mechanical equivalents which maybe reasonably included within their scope.

I claim as my invention:

1. A collapsible T-square having a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiifening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square and to said sections.

2. A collapsible T-square having a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiffening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square' and to said sections, said sections having engagingtongues and cavities.

3. A collapsible T-square having a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiffening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square and to said sections, said sections having engagingtongues and cavities, said rod having a plurality of complementaryjoined sections.

4. A collapsible T-square having a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiffening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square and to said sections, said sections having engagingtongues and cavities, said rod having a plurality of complementaryjoined sections, and being joined by means of inner engaging threadedstuds and threaded cavities formed on said sections.

5. A collapsible T-square having a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiffening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square and to said sections, said sections being hinged to eachother whereby said sections can be folded to a collapsed position.

6. A collapsible T-square having a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiffening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square and to said sections, said sections being hinged to eachother whereby said sections can be folded to a collapsed position, thehinges between said sections being progressively longer toward the headof said T-square to provide increased folding room space between thesections.

7. A collapsible T-square having. a transverse head and a lengthenedportion joining said head, said lengthened portion having a plurality ofjoined sections, means for collapsing said sections to occupy a minimumspace, means for stiffening said sections when in operative position,said stiffening means being positioned adjacent to said sections, saidstiffening means including a rod, said rod being secured to the head ofsaid T-square and to said sections, said sections having engagingtongues and cavities, said rod having a plurality of complementaryjoined sections, said rod being threadably engaged with said head, theend section of said rod having an opening for loosening said threadedengagement, a knurled turning head attached to said rod, bossesextending from said sections receiving said rod.

References Cited in the file of this patent UNITED STATES PATENTS398,501 Duflin Feb. 26, 1889 741,861 White Oct. 20, 1903

